Semiconductor manufacturing processes include a wafer fabrication process. Generally, a wafer fabrication process includes a photoresist coating process, a developing and baking process, an etching process, a chemical vapor deposition process, an ashing process and so forth. In addition, a wet cleaning process is performed using chemicals or deionized water (DI water) to remove various contaminants attached to a surface of a substrate during these processes.
After a cleaning process is performed, a drying process is performed to dry chemicals or DI water remaining on the surface of the substrate. A spin dryer and an isopropyl alcohol (IPA) dryer are used as apparatuses for drying substrates. The spin dryer uses a mechanodynamical rotatory force to dry semiconductor substrates, and the IPA dryer uses a chemical reaction of IPA to dry semiconductor substrates.
A typical spin dryer uses the rotation operation of a spin head to dry substrates. Considering impurity particles with the trends toward higher integration density of semiconductor devices and larger diameter of substrates, the spin dryer cannot evade disadvantages such as watermarks formed on a dried semiconductor substrate.
For this reason, the IPA dryers are widely being used. As mentioned above, the IPA dryer uses a chemical reaction of IPA to dry substrates. That is, the IPA dryer vaporizes an IPA solution and substitutes DI water with the vaporized IPA solution to perform a drying process.